Just a few days ago, our world witnessed history, as the Ingenuity helicopter took off from Martian soil and hovered for about 30 seconds before coming back down on the ground. To some, this may not mean much, but for scientists, this event is a scientific breakthrough, for many reasons.
There are several technological challenges to conducting a helicopter flight on another world. First, and most significantly, helicopters need an atmosphere to fly.
The blades, or "rotors" of a helicopter must spin fast enough to generate a force called "lift." But lift can only be generated in the presence of some kind of atmosphere. While Mars does have an atmosphere, it's much, much thinner than Earth's — about 100 times thinner, in fact.
Flying Ingenuity in Mars' atmosphere is therefore the equivalent of flying a helicopter on Earth at a height of 100,000 feet. For reference, commercial aircraft fly between 30,000-40,000 feet above the Earth’s surface and the highest we’ve ever been in a helicopter on Earth is 42,000 feet.
More about this over at Space.com.
(Image Credit: NASA TV)